Electronic counting device



5 Sheets-Sheet l LAMPS P. GILBERT ELECTRONIC COUNTING DEVICE Jan. 12, 1954 Filed Maron 12, 1951 INI/ENTOR. PHILIP GILBERT W ,af/@Wwf FIG. 2.

Jan. 12, 1954 P. GILBERT ELECTRONIC COUNTING DEVICE 5 Sheets-Sheet 2 Filed March l2, 1951 IIJ Jan. 12, 1954 p, G|| BERT ELECTRONIC COUNTING DEVICE 5 Sheets-Sheet 3 Filed March 12, 1951 Jan. 12, 1954 P, GILBERT 2,665,846

ELECTRONIC COUNTING DEVICE Filed March l2, 1951 5 Sheets-Sheet 4 Jan. 12, 1954 P. GILBERT ELECTRONIC COUNTING DEVICE 5 Sheets-Sheet 5 Filed March l2, 1951 INVENTOR.

GILBERT PHIILIP Patented Jan. 12, 1954 PhilipGilbert, Ferguson, Mo., assignor to niversal Match Corporation,

ration of Delaware St. Louis, Mo., a corpo- Appl'ieatiniuerh 12, 19571, serian No. 215,175

This invention relates ingeneral tocertain new and useful improvements y"in electronic counting devices and, more particularly, vtoca counting devicecapaole of` counting directly by units and tens in decimal orden In many diverse and different types of situations, it is necessary to determine the total quantity of a given physical eiect, phenomenon, or factor. For example, in photographic work, it is highly desirable -to measure the Volume of light Whichfalls upon the given object. This problem is frequently encountered `in making photographic exposures both in printing from already iinished negatives, as Well as in exposing the negatives inl acamera in the rstinstance. Thel problem in photographic work is particularly critical `becauseprecise results cannot be photographically reproduced with sufficient accuracy for commercial activities unless it is possible to 4know that an almost exact yand reproduciblev quantity of light can be employed in making the exposure.- Since photographic lights are energized electrically and electric potential uctuates from moment tomoment the intensity of the light Will vary or iiuctuate during any period of exposure, It is,therefore, not possible toy obtain precise photographic exposures through the useof a timer, however accurate, in-

asmuch as relatively smallvoltage iluctuations result in illumination fluctuations ot v much greater magnitude, which, in turn, results in negative density variations of comparably great magnitude.V f Y It is, of course, not only necessary to measure the volume of light during the exposure, but it is also necessary to integrate the intensity of the light'in terms of time so thatthe result may be employed to producesome useful result, such as, for example, trippinga relay which will close the shutter of the camera or. in some other way mechanically terminatethe exposure at "the end `of the given period. To be more specii'lc, suppose that in making photographicplates, it, is

desirable to expose afplate to a given quantity of light for a predetermined period the operator will, of course, know what amount-.oferposure is desired having determined this amount either by observation or by y previous experiments in which the exposure was too great or too small. It, therefore, becomesnecessary for the operator to be able to set an; exposure determining device to the amount of-exposure desired, so thatwhen the amount of exposure, thatis tofsay, the integral of intensityf-in terms ottime, hastbeen reached the exposure will be automatically terminated.

i9 claims. (C1. zas-132) Although heretofore many efforts havebeen made to provide electronic integrators,-which will initiate some mechanical action at the conclusion of a pre-set count, such integrators or counters, have been unreliable and vinaccurate, as when, for example, they are pre-set by moving a pointer overa dial which both introduces parallax and relies uponV theaccuracy of the memory of the operator to reset them'to `the same result,ror which are not capableof having the desired result set up directly in thefdesired number, but must, instead, employ. some arbitrary reciprocal or compensating series of digits. Such expedientsof course, apart from reliability and accuracy, are extremely diincult touse-and require a skill far beyond that of the ordinary It is, therefore, -one of the primar-y` objects of the present invention to provide an integrating electronic-counter whichis relatively -simple in construction and highly-reliable in operation and which can be employed to--initiate some mechanical result when a predetermined count has been reached.

It is anotherrobject of theY present Iinvention to provide an electronic counter ofthe .type stated which can be set to some-predetermined count so as to be capableof vinitiating a mechanical result When such pre-set count'is reached.

`It is a'further object of the present invention to provide a decade-type electronic counter in which any number .of successive. `decades-may be cascaded so as `to supply axcounter having almost limitless range if such be desired. Y I

. It is anothel` object of thepresent invention to provide an integrating counter vin which a predetermined count may be set directly-without reference to reciprocals, complementary numbers, phantomnumbers, compensating factors, or other arbitrary mathematical expedients and which is, therefore, extremely simple and accurate in actual use, Y i.

With the above andy other objects in view, my invention resides in the novel features of form, construction, arrangement, and .combinationr of parts presently described and pointed out in the claims.

In the accompanying drawingsv, y al.

Figure 1 is a front elevational viewy of an electronic counter constructed in Va.ccordance-with and embodying the present inventionand show? ing such electronic counter-.schematically connected for determining lightintensity; ,l y;

. Figure 2 is a wiringgdiagram,showing Ythe sensing circuit or `scicalled fpulsefgenerator in conjunction with the light measuring photocells counter constructed in accordance with the present invention and showing the relative relationship between the several components thereof; and

Figure 6 is a schematic diagram illustrating the relationship between the various components of a decade in terms of the sequence of electronic results occurring during a single cycle of operation.

Broadly speaking, the present invention employs some sensory apparatus which is electrically responsive to the physical phenomenon or rnechanical factor desired to he measured, such as, for example, aphotocell, which is Acapable of emitting an electrical current-directly proportional to the intensity of light falling upon it. The output of the sensory device, such as the photocell, for example, is fed into a pulse generator' which will emit a single pulseas soon as a sufficient quantity of output from thephotocell, or other device, has beenrfed into it. It should be understood that the pulses emitted by the pulse generator are not uniformly periodic in terms of time, but are rather a measure of the integral of intensity in terms of time. These pulses are fed into a series of decades, each of which may be characterized as a ring-Of-five and scale-of-two electronic circuit with the addition of ten signal lights and ten switches which operate in conjunction with a coincidence circuit and an interdecade circuit. The ten switches correspond to the successive digits in the seriesV from zero to nine and are selective in the sense that anyonerof the ten switches may be set to on position, but only one of such switches in any decade can be so set. Y,

The coincidence circuit in each decade contains a triode tube which is adapted to conduct current as long as a positive potential in excess of its cut-off or threshold potential is applied to its grid. The outputs from the coincidence circuits of all the decades are paralleled into the coil of a relay which, as long as itis energized, holds closed a switch controlling mainline current to be disconnected at the end of the Vcount,.so to speak. When a selected switch is set to on position in a given decade the coincidence circuit of that decade will be unaffected by all pulses coming into the .decade except the one pulse which corresponds t the selected number. For example, if the number seven is set into a given decade by setting the switch corresponding to the digit seven, the triode tube in the coincidence circuit of that decade will cut 01T on the seventh pulse and remain oi until the eighth pulse, whereupon it will conduct again.

The interdecade circuit in each decade also contains a triode tube which will transmit an interdecade pulse responsive to every tenth input pulse received by that decade. Thus, every time ten pulses have been fed into the units decade the interdecade circuit thereof will function to transmit a single pulse into the tens decade, and similarly, every time ten pulses have been fed from the units decade into the tens decade the interdecade circuit of the tens decade will function to transmit a single pulse into the hundreds decade.

This arrangement, of course, may be cascaded through any number of successive decades which may be necessary to provide a counter having desired upper limits or capacity. The several decades are so arranged that every incoming pulse will be accurately counted and will accumulate toward the ultimate end result,

As previously pointed out, each decade can be set by manipulation of the switches associated therewith to respond to a given number. For instance, if the number two hundred thirty four should be the number at which the counter should initiate the desired mechanical result, the number four switch would be set in the units decade, -thenumber three switch would be set in the Amits an interdecade pulse into the tens decade on every tenth pulse received from the pulse former and the output from the coincidence circuit of the units decade is cut off on the fourth pulse received from the pulse generator and remains off until the next succeeding pulse is received. Similarly, on the tenth interdecade pulse received from the rst decade, the interdecade circuit of the tens decade transmits Van interdecade pulse into the hundreds decade and meanwhile, on every third interdecade pulse coming into the tens decade the output from the coincidence circuit of the tens decade cuts off and remains oi until the next interdecade pulse is received. Since the tens decade counts by tens the third interdecade pulse received by it corresponds to the thirtieth pulse received by the units decade. Finally, the output from theY coincidence circuit of the hundreds decade would be interrupted on the second interdecade pulse coming into the hundreds decade fromv thetens decade. This means that on every fourth pulse received from the pulse generator the coincidence circuit of the units decade will cut off. On the thirtieth pulse coming into the units decade, or in .other words the third interdecadepulse passing from the units decade to the tens decade, the output from the coincidence circuit of the latter will cut off and remain off until the fortiethpulse. Hence, on the thirty-fourth pulse the coincidence circuits of the units decade and th-e tens decade will be cut off, so that only the coincidence circuit of the hundreds decade is condr-.cting an output current and the relay continues to be held open. On the two hundredth pulse coming into the units decade or, in other words, the second decade, the coincidence circuit of this decade cuts oit and remains oi. Thereafter', on the two hundred thirtieth pulse the coincidence circuit of the tens decade cuts ofi" and finally on the two hundred thirty fourth pulse the coincidence circuit of the units decade cuts oif. Hence, on the two hundred thirty fourth pulse all coincidence circuits'are simultaneously cut on and the relay drops out, thereby producing the desired mechanical result and at the same time cutting off the input from the pulse former to the units decade.

Referring now in more detail and by reference character to the drawings, which illustrate a' preferred embodiment of the present invention,v A designates a direct-setting integrating electronic counter comprising a rectilinear cabinet i having va front panel 2 provided with a main switch 3 having a bulls-eye signal light d. Also mounted lnet I are three spaced parallel decades .8

shownxdiagrammatically inFigure fi'.` l

Alsoiset-.into the irontpanellA and extending inwardly therefrom into the :interior of the cabi- ,of and `I 0, each` of 4identicalconstruction `and being the tunits. decade, the tens decade, ands the .hun-

dredsA decade, respectively.` Each of the. decades 8, .9,1and IIJ is-'providedfwith'a visible iront panel I I providedwithltenzyertically spaced neon lamps Lo, lLrfLr;y L3, L4',;-L5,Ls L7, Ls,=.zalld Lair-AISO mounted in and Yprojecting*,through each decade ypanel IIl are ten push` button switches'uSo,` S1, S2,

S3, vS4',` Ss, Se, S7, Sa, and ,.Ss, resp,ectively,',located -in juxtaposition totthe corresponding lightsvLo, E;- The switches from Soto S9, -inclusive,-,are ,double polefsingle .throw switches andare `mechanically interlocked in any suitable andconventional manner so that when oneswitch is pushedin and thereby set into on position, any other switchy which is vin fon position will, be released automatically.

Thus, only one such switch-,will be fon at .any time. The mechanical arrangement accomplish- ,ing this particular result is wellfknownand does not form a part .of `thepresent invention.

Each ofY the decadevpanels His also provided with asingle v'polefsingle throw counter-light ,switchv I2, which merely lfunctions to permit the .operator to turn thecounter-l-ights Loto La, in-

clusive, oi or onfat willwithout otherwise interrupting the.- normal t,functioning A:oithe .counter A. This is, a` particularlydesirable function where the counter `is used in photographic .dark room for photographic printingcontrol. In

lsuch applicatonslor uses the ilickering of .the

counter-lights Loto Lninclusive, would, of course,

fog exposed sensitive;materials-For other purposes as.. presently ,willl be.V discussed, it is desirable to employlthe counter-.lights in order to rbe able to read .variouscounts andotherjresults visually. `In thisconnectionitalso should be point- 4,ed out that each of .the decades, 9, and Irare preferablypthough not Inecessari-ly, constructed as an integral .assembly upon a-unitary chassis ,and can'be slid in andout ofposition on` the ,main 4panel 2 for, convenience inmanufactu-ring assenrblyv and repair@r ThisH particularV arrangement, however, is not significant .and the present invention is in no manner limited thereto.

a pulsegenerator J3, a powersupply unit I4,a control.. relay I5,.a nd arpower relay' I6. Also mounted atany convenient location, eithery withtwo conventional double prong plug-in outlet receptacles I1, I8.

I Power l.supply unit suitamy .mounted-withinthe .cabinet upon Y, Lseparate i andy individually removable chassis are iin the cabinet I or onthe back wall thereof, are Y The power supply unit' I4, as shown in Figure 6,- comprises a conventional Y full-wave voltage doubling circuit made up of rectiers :c and y and 'capacitors C10i and C11, together with, surgelimitingresist'or R13, Vso -asv to 'produce approximately 25,0 v. D. Cqfrom the 120 v. A. Celine.

'Across this'D. C; power supply, a double tricde vacuum tube, with-both sectionsin parallel, isso connected tovresistor'sR1o,-R11, and R12, asto coinprise acathodefollowerV voltage regulator, vso as tomaintain a substantially rconstant potenti-al vof 155 v. across resistor R12 although the current which is connectedacross the other types of y through R12 varies due toitsjcozinectiontov other circuit. elements. Also forming a part ofthe power unit I4 is a transformer i9, the primary-of 12.0 v. A. C. leads from `the main switch and being designed to produce an output Vpotential of 6.3 v. A. C. across its secondary.A The v. A. C. line is also provided with three hot ilarnent leads F1, F2,` F3, and

a common return filament lead F4; Interposed Vin the hot lament leads F1, F2, and Fs, arere sistors R15,R1s, and R17, for reducing the voltage -inl the lament lines to the appropriate'value. The hot filament leads F1, F2, and Fs, arerespectively connected to the hot'lament supply lines 'of the decades 8, 9, and I0, respectively, andthe return filament lead F4 -vis'connected incommon Ito-the rreturniilament leads of all the decades,

9,-'and 10. The filament connections within the -decades are the conventional series string and,

hence, not specifically s own.

Pulse generator The pulse generator I3, as shown in Figure 2, comprises a neon-gas discharge tube N1, Ia gas lled thyratron tube N2, and a double triode tube N3 connected in a network of resistors R13, R19, R20, R21, R22, R23, R24, R25, Rza-R27, R28, and CondenSeIS C14, C15, C16, C17, C18, andCui. Y

Associated with the pulse generator I3 are two photocells 2il, 2l, either of which may be selected through. the cell switch 6 which places the selected cell'in` operation ,by permitting it to be connected to B+ upon the operation ofrelay I6. At the same time, switch 6 selects Ythe one of the two output receptacles to operate the particular device associated with the chosen photooell. This is a convenient arrangement where the counter A is being used as an illumination controlling device in connection with photographic work on a commercial'scale for in such applications one of the photocells may be located within the dark room, where certain types of photographic operations are being performed, and the other photocell maybe located in the exposure room 'where photographic operations are being performed, and the operator can switch, at will, from one cell tothe other as the needs of the moment may require,

The pho'tocells 28, 2 I, as is well understood, will act, depending upon which one has been selected for operation, as a valve or control means to regulate the current owing from the B+ lead into Vthe vcapacitor C14. This output is, of course, a fluctuating current which varies responsive to variation in the amount of illumination vfalling upon the operative photocell. This output vcurrent from the photocell charges up the capacitor C14 until the striking potential of the tube N1 is reached. The discharge of the tube N1 through resistor R20 transmits a positive pulse to the grid of the normally biased-off thyratron N2 which then fires, completing the discharge of 'capacitor C14 and thereby emitting a short negative pulse which is amplified through the tube N3 and is fed into the input lead 22 running into the units decade 8. y

The thyratron tube N2 uniquely :zo-operates with the neon tube N1 to produce an output pulse signal having shorter rise time, greater amplitude, and lower impedance than the-type of signal obtained merely lfrom the relaxation) ofthe gas diode or neon tube N1. Heretofore someefforts have been made to employ a vgas diodev alone .to generate pulses through the .discharge biancapacitance circuit, but the base potential to which gas diode tubes ordinarily discharge is relatively inexact andfvaries appreciably from'discharge'to discharge, so'that'the functioning of such a circuit is not reliable Vbecause the basexpoint to which the tube ddischarges is not uniformly .re-

falling on the photocell 2i (assuming that the photocell 2l is the photocell selected for operation) is of comparatively high intensity for a given period of time the output from the photocell 2I, which is fed into the capacitance network of the pulse generator I3, will be relativeh7 high so that the capacitance network will charge up more rapidly and, hence, discharge with greater frequency producing a larger number of pulses within such given period of time. On the otherhand, if the intensity of light falling upon the photocell 2| is relatively low for any given period of time the output from the photocell 2I will be comparably low and the capacitance network of the pulse of the generator I3 willcharge up at a slower rate, thereby producing@ lesser number of pulses within suchjY given period of time. It will thus be seen that each Ypulse is a measure of aunit of quantity andrby counting the number of pulses generated it is possible to Vdetermine the quantity of light falling uponthe photocell.

Decade counter umtsv Each of the decade counter units 8,29, and It t are identical and, therefore, only the units decade will be described in detail herein.

The units decade 8, as previously noted, includes ten counter-lights Le, L1, L2, L3, L4, 115,115, L2, L2, and L9, and ten number-switches S11, S1, S2, Ss, S4, S5, Se, S7, Ss, and S9, Connected as shown in the wiring diagram Figures 3A-3B.

The units decade also includes five double triode tubes T1, T2, Ta, T4, and T5, each of which is connected in a network consistingvof resistors R11,

R2, Rs, R4, R5, Re, R2, and condensers C1, C2, C3, C4, to form a trigger circuit, and the ve trigger Acircuits are successively ,connected to each other and the fifth trigger circuit is regeneratively connected back to the rst trigger circuit to form a fring-of-ve arrangement.

It will be noted by reference that the cathodes of all the tubesrT1, T2, Ta, T4, and T5, are linked .together in .common cathode Vcoupling circuits by means of the leads X6, X2, the resistors R22, Rao, and condensers C20, C21.

AThe right hand grids 23 of each of the tubes T1,

T2, T3, T4, and T5, are connected through condensers C1, C2, to the input lead 22. The first tube T1 is also connectedthrough the resistor R1 to the lead 24 coming from the reset-start switch 6 and thence to the B lead, whereas the grids 23 of all the other tubes T2, Ta, T4, and T5 are connected directly to the B- lead. Similarly, the left hand grids 25 of all five tubes T1, T2,

T3, T4, and T5 are connected in common directly to the B lead. Thus, when the reset switch is depressed the grid 23 oi the first tube T1 is disconnected momentarily so that the right-hand side, so to speak, of this tube T1 begins to conduct.

up in such configuration that their 'left-hand sides, so to speak, will be conducting.

When the first pulse emitted by the pulse generator I3 travels along the the input lead 122 it will be simultaneously imposed' upon lthe grids 23 of all five tubes T1, T2, T2, T4, and T5,v but since only the first tube T1 is in such configuration that its right-hand side is conducting only that tube, namely, the tube T1, will be affected by this negative pulseand the tube T1 will be caused thereby to switch over so that its left-hand side begins to conduct and correspondingly the right-hand side ceases to conduct. As the tube T1 flips over, so to speak, a transfer pulse is transmitted from the plate 26 and applied to the grid 25 of the next succeeding tube T2. Thereupon, such next succeeding tube T2 flips over so that its left-hand side which was conducting now ceases to conduct and correspondingly its right-handA side which was not conducting begins to conduct. In other words, the right-hand side of the tube T2 becomes conditioned to receive the next succeeding pulse travelling along the input lead 22 and simultaneously the right-hand side of the tube T1, having now ceased to conduct, is no longer in condition to be affected by negative pulse. Similarly, nothing has happened to the conguration of the remaining tubes T3, T4, and T5, so that-they also are not affected by negative pulses on the input lead 22. The second pulse lon the input lead 22 will, therefore, aifect'the second tube k'T2 and cause it to nip over again to its initial configuration in the same manner aspreviously described in connection with the response of the tube T1 to the first impulse and this change Of configuration of the tube T2 will in turn produce a transfer pulse which is passed on to the next succeeding or third tube T3. Each successive tube will thus become, in turn, affected by succeeding negative pulses on the input lead 22. The fifth pulse, which induces a change in configuration of the fifth tube T5, will be'regeneratively transmitted along the lead X4 back to the rst tube T1 conditioning the latter to receive the sixth pulse, so that the five tubes, in effect, count by fives in continuously successive order as long as negative pulses continue to come in off of the input lead 22.

The transfer pulse, emitted by the fifth tube T5, isalso applied to the grids 21, 28 of a double triode tube .T6 which is connected, asshown in Figure 3B, in a conventional trigger-circuit network' consisting ofresistors R51, R32, R33, R34, R35, R35, and condensers C22, C22, -substantially similar to the previously described trigger networks associated with the tubes T1, T2, T2, T4, and T5. The cathodes of the tube Ts are connected in common through a resistor R37 and a condenser C24 to the B- lead.

Because the ring-of-five circuit will emit positive as well as negative pulses and the negative pulses are the only ones which are significant for counting purposes it. has been found necessary in connection with the present invention, to interpose a double diode tube D which functions as a clamping tube or rectifier `te transmit only the negative pulses. trigger tubeTe will receive only the negative transfer pulses emitted by the tube T5. In other Hence, the

9. words, 'the 'trigger tube 'Ts will receive Ia Ytransfer pulse responsive to every fth negative pulse coming .in from the input line 22. It Will 'also be noted by reference Vto Figure A3B that the lefth'andgrid 2'! of the tube Te is connected through the resistor R36 to the reset line '24. Hence, when the'reset switch. is pressed'to condition the 'tube'T1, as previously described, and the trigger tube T6 Will lbe simultaneously conditioned -or set yup in a .configuration such that its left-hand side is Conducting and its right-hand side .is off Hence, the rst transfer pulse impressed 'upon the trigger tube Te will cause it to change its configuration so that its left-hand side 'goes off and its right-hand side begins to conduct. Similarly, on the `next transfer pulse received by the tube T6, that is 'to say the transfer pulse corresponding to the fth negative pulse coming in from the input lead 22, the trigger tube Ts will again change its configuration so that its right-hand side ceases to conduct and its lefthand side begins'to conduct, that is to say, returns to its original conguration.

Y'Also Aincluded Within `the units decade -8 is a single triode tube Tv which functions as an interdecade discriminatory tube of Vso-called polarity descriminator having a `cathode 21 which is connected through a resistor R30 to the B- lead. The grid 38 of the tube T7 is 'connected to the resistor R29 and the resistor R40 to the B lead and is, therefore, normally impressed wit-h .'astrong negative bias which V-is fbelow its normal cut-off potential. Hence, the -interdeca'de .discrimina-tory tube T7 'will ordinarily be 1in a non-conducting -or ofi condition. 'The grid :3Q of .the -interdecade discriminatory tube T1 Vis :connected by la capacitor YC25 to a lvoltagedividing network consisting Yof la resistor R42 and a .resistor R43, the voltage dividing network being `connected across the plate on the 'righthand side o'f the .trigger 'tube Te andthe 250 -v. B+ flead. The interdecade discriminatory tube T7 together 'with the 4resistors R42, R42, 'and capacitcr C25 may be referred to, -for convenience, as the vinterdecade 'transfer circuit. As has been above pointed out, `the plate of lthe rightlhand side of fthe .trigger tube T6, in effect, emits a negative :pulse .responsive lto every lfth input pulse .coming into the fring-of-ve Icircuit 'from the input Alead 22 fand :a positive pulse in response to .every ltenth pulse -coming vinto the ring-of-nve circuit from the input 'lead 2-2. The negative 'pulses emitted by the plate il Aof the trigger T6 do not have -any leifect on fthe condition of the interde'cade discriminatory tube Tv since its grid is already strongly negative. However, :the positive pulses, which are momentarily impressed upon -the grid 3e Yof the interdecade v'discriminatory tube Tv responsive to every tenth. pulse coming into the ring-of-five ycircuit frorn the input 'lead -22 zcause the interdecade discriminatory tube T1 to conduct and hence the voltageon .the 4plate-3l thereof `drops sharply producing, yin effect, -a sharp negative `pulse in the output lead X14, which is connected to the input lead 22 ofthe nextsucceeding decade I0.

Selector switch circuits As has been above pointed out, veach decade includes 'ten selector switches S0, S1, S2, S3, S4, S5, vSe, S1, S2, and S9, or Vnumber switches as vvthey may :be called, `and Ithe visible voperating buttons thereof each labeled -`with va digit ranging from zero Vup Lto nine, respectively. The severa-l selector Switches So, S1, Sz, S3, S4, S5, SG,S'1,`SB,

10 and S9, fare connected, as .shown in Figures 3A-3B, through an isolating network consisting of resistors R44 and R45 `to the grid 32 of a coincidence tube Ts, which is a vacuum tube of the single triode type substantially similar to the single triode tube T2.

In connection lwith the tubes T2 and Ta it should be noted that for convenience in manufacture it vis possible to eliminate the use of vtwo single 'triode tubes and substitute therefor one Idouble triode tube of the same type as the double triode 'tube v.used :elsewhere in the device. In this case, of course, the two halves of the double triode tube will lbe entirely .independent of each other and will respectively function exactly 'in ythe Vvmanner of the -tWo separate tubes Tv and T8. The 'use of such a double triode tube may, 'for manufacturing purposes, be considered convenient and economical since it is thereby possible it'o use the same kind Aof tubes throughout the device rather than to employ various difierent kinds of Vtubes at different points in the circuit. This latter expedient is, of course, common practice and 'has noparticular bearing upon the Vpresent invention.

The cathode 33 of 'the coincidence tube T8 is connected directly to the 155 v. B-llead and the plate 34 is connected through lead X13 to the control Irelay fl5, as will presently be more fully described.

The coincidence tube T2, having its cathode held at a potential of 155 v.,yvil1 conduct current as long Aas a -positive potential in excess of 155 v., minus cut-olf bias, is supplied to the grid 32.

The operation of the selector switch circuit can thus 'be understood by reference to the schematic drawing 'in Figure 6 wherein the tubes T1, T2, T3, T4, T5, Ts, Tf1, and T2 are shown. In Figure '6, for purposes of clarity, only the transferepulse emitting side of Ythe tubes T1, T2, T3, T4, and T5, are considered and leads from the transfer-pulse emitting rplates thereof are schematically shown `as being connected directly into the two selector switches associated therewith. Furthermore, the selector switches are not shown in numerical order, .but are .illustrated in such a manner that .the two selector switches Se and S5, which are .associated with the tubes T1, are located more `or less opposite to the tube T1. Similarly, the two selector switches S1 and Se are shown in opposite alignment, in Figure' 6, to the tube T2. Finally, the series of vertical dotted llines form graph-intervals or spaces associated with the digits ranging from zero to nine and thus schematically indicate nine successive pulses coming into the ringmf-ve circuit so that it is possible to trace the condition of all the several circuits after each particular pulse. For convenience in illustration a voltage curve is drawn above each plate lead. It will be noted that the lpulse -emitting Vplate elements of the tubes T1, T2, T3, T4, T5, and Ts, all vary between ra maximum of 240 v. and a minimum of v. depending whether the .particular tube is Non?) o. l

Each of the selector switches So, S1, S2, S2, S4, S5, Se, Sv, Sa, and S9, being a single pole double throw switch, may be said to have two current paths through it. One pole of each of the switches is connected through the common lead X10 to the external side of the resistor R45 and the other pole is connected either to the lead X11 or the lead X12 to one vor the other of the plates of the trigger tube Te. It-w'ill benoted that the selector switches S0, S2, S4, Se, S2, are connected tothelead X1zandtheselectorswtches S1, Sa, S5, Sv, and Se are 'connected to thelead X11. Hence, one current pathway through all of the Selector SWtChesSo, S1, S2, S3, S4, S5, Ss, S7, Sey andv S9, carries current from either one or the other of the plates of the trigger tube Ts. The "other" current pathway in each of the selector SWtcheSSo, Si, S2, S3, S4,` S5, Ss, S7, Se, andSQ are harnessed'together in pairs, as best illustrated in Figure, and are thus connected respectivelytdthetubes T1, T2, T3, T4, T5.VV The other side'ofthistecond curve pathway through each 'of the selectorv switches Sn, S1, Sz, S3, S4, Ss, Se, Sv, S, and Saislconnected by'a common lead X9 tothe external end of the resistor R44.

Suppose'for example, the selector switch S'z of the units ldecadev 8 is vpressed down or set into "on position. All of the other selector switches, as 4hasbeenabov'e pointed out, are open. Therefiore) the plate' potential of the righthand half ofthe tub'e T3 (reference being to'Figur'e 3A) is connected across one `side ofthe is'olating'network -a'nd'theplate'potentialf plate 3i, that is to say, vthe'right-"ha'nd'plateof trigger T5, is connected across the other side of theisolating network. At the first input pulse, 'als will be seen 'by following down the space' between the first two dotted lines'in Figure 6,'that is tosay, the space associated with the digit 1, the plate'potential from the tube T3 is at 240 v. and the plate potential 'from' the trigger tube Te isk also 240 v. Thus, a `'potential of 240 'vg'isapplied to'both sides of the isolation network which is substantially more vpositive thanthe' cathode potential or" 155 v. so fthe'tube Ta remains on On the second iin- .pulse the plate potential fromftube T3 is 'down t'o 130V. while the plate potential from tube Ts remains at 240 V. Thus, a potential of 240 V. is applied on one side of the isolating network and .a potential of 130 v. is applied on the other side thereof; TheV average of these two potentials is 185V.' Therefore, the potential applied upon a 'grid'ofV the coincidence tube Ts is 185 v., which is still substantially more positive than the cathode vpotential of 155 v." Consequently the coincidence tube Ts' remains on^, or' conducting; Similarly, at' the third inputpulse the vplate-potential from the tube'Ts remains at V240 v. Since potentials of 240 v. 'are now applied on' both sides of the yisolating network theY potential applied to the grid of the coincidence tube Ta' is now 240 v. and again the coincidence tube Ta remains en A similar situation exists through the fourth pulse. At the fth pulse the plate potential from the tube T3 remains at 240 v'; but the plate potentiai from the trigger tube'Ts `drops to 130 v. Again, potentials of 240V. and 130 'v., respectively, :are applied across the `isolating network resulting in "ani averagepotential Aof 185 V. which is applied to the g'rid. ofi the Ycoincidence Vtube'Tc and the sarne"'condition` prevails upon the sixth pulse;

Onthev seventh pulse, however,V the plate. potentialfro'mthe tube T3" drops to y130 vv. andthe plateY potential fromtheft'rigger tube Te remains at 130 v. Consequently, potentials of'lSO'v., re spectively, are appliedto both sides of the isolatingnetwork andapotential of 130m is, therefore, applied tothe grid ofthe-coincidence tube Ta'.L Since this Voltage biases the. grid substantially-belowcut-off-,-the coincidence tube T8 will cease to conduct current from the control relay I" through -the lead Xia untilthe next succeedingpulsethat isto sayftheeighth pulse; comes into :they circuit... ,It-shouldvbe noted in-this connectionthat thepulsesthemselves are of. rela- 12 tively short duration, but the condition initiated by and resulting from the pulses 'is stable until it is changed by thenext succeedingpulse. The circuits may thus besaid to be switched from one condition of stability to an alternative condition of stability by the various incoming pulses.

'As'has been heretofore pointed out, the several leads X13 from the diierent decades 8, e, and l are connected in common to the energizing coil of the control relay l5 and, as a result, the control relay I5 is held closed so long as any one of the three coincidence tubes Ts are conducting current. When, however, the coincidence tubes Ta of the three decades all are simultaneously cut off or in coincidence, so to speak, no current will be transmitted to the control relay I5 on any of the leads X13. Hence, the vcontrol relay I5 will drop open.

Control circuits As will be seen by reference toFlgur'e 4 the control relay l5 operates a pair of contacts which are in series with a conventional lock-in switch 35 formingapart of the power relay I6. The energizing coil 36 of the power relay VS is connected at' one end directly-to one side of the 120 v. A-.-C. line' and atits other end through the reset switch to the other sideofcthe A. C. line. The power relay also includesa'photocell switch 3? and anv outlet switch 38.

The blade of the photocell switch is Vconnected through the cell switch ii to the photocell 20, 2|, and-the two poles of the photocell switch 31 are respectively connected'to the B+ and B leads, the latter, -in effect, functioning as a ground. The blade of the outlet 'switch 38 is connected directly to the one side ofthe 120 V. A. C. line pole-of the outlet switch 38 and "is connected in common to one contact terminal of each of the outlets I1, I8.V The other contact terminals-of the outlets l1, I8, are respectively connected through the cell switch optionally to theother side of the 120 v. A. C. linen-For convenience the focus switch 5 isconnected so as toby-pass the outlet switch 38 whenever desired. Y

When the reset-start switch 'l is closed the coil 36 of the power relay -will Vbe energized and the relay -will be closed, thatl is to say, the lock-in switch I6 will befclosed so that the relay stays in closedposition.v f Similarly, the photocell switch 31 will befclosed so that one -or the other of the photocells 20,Y 2l, will be connected to the B+ line depending Vupon the position of the cell switch l.V Finally, the outlet switch 38 will be closedso that the solenoid operated shutter or other mechanical device which-is Yto be actuated by the counter A Vcan be plugged' into one or the other of the outlets l1, t3, and .will'function therefrom-V 'Where as herein described, the electronic counter A is used for photographic work ,a conietionalsolenid actuated shutter (not shown) may pepiugged into the moet le, 'for' ga'mpm, and willAk thus Y be associated c with` the photocell 2l in the exposure room. Similarly, a printing light located in the dark room may be plugged into the outlet l1 and thus,associatedwithphotocell 20 which may also be located in the dark room. Hence, by proper manipulationof the cell switch .6 photographic print operations in the darkroom or photographic exposure operations inthe camera room may, in the alternative, be controlled by the counter A. l 1

1@parution .Forpurposes of f describing the :operation :ofthe integrating felectroni'c counter ,-A .it will be assumedhereinthat the device is employed in .conjunction with photographic Cexposure work. `It should be '.understo'od, however, `that V.the present invention is by'no meanslimited to photographic applications, inasmuch 'as the counter Acan b'e used 'to -control `any type of l electrically 'operated device in response tto an I integrated `measurement where the 'quantity to Abevmeasurediis capable of being'measuredin terms o'f electricalresponse IIn the illustrative example here'in 'employed the photocells 20, 2l, are merelyfone type of Vsensory device capable-of emitting ran electrical 'impulse which vis 'a 'measure *of f an 'external phenomenon 4If the-counter A, therefore, is -to beuse'd tfor determining exposure-time in making photographic 'reproductions fin a commercial Iphotol graphic plant, 'a 'solenoid vactuated camera shutter Acan "'b'e 'plugged -into `the loutlet T8 'and the photocell 2"! pla'ceupon the vcopy'board 4facing the -exposure"'light E 'so vthat'the sameamount of lightwhich impinges upon the photographic work l will 'also fallupon the `sensory element of the photocell 2l. It will, of course, '"be understood that the cell lswitch'l isset to :the position shown in Figure 2. The camera may then be .focused by moving the focus .switch 5* into the position l shown in Figure f4, thus *opening "the shutter. When the 'camera has been'properly'focused in the conventional -manner ".the 'focus switch '5 is shifted back to expose position, closing the shutter.

Meanwhile the operator, with due regard for the relative speed fof the sensitive material to be exposed "as well asthe effective aperture of the camera diaphragm, will determine 'the amount of exposure, generally through the following pro- -f cedure: In changing from 1.a timer to an integrating `,photometen the photographer usually nds it convenient to .fit a diaphragm .to the photocell tocontrol the amount of lightimpinging upon it, so that, with thellight sources which he uses, the counting rate is yapproximately one count per second. Thus, he is able to convert his established exposure times -into integrator counts. Suppose, for example, .that .he .determined .the .amount of exposure to be two hundred thirty-four units. He, thereupon, sets the .-number two hundred vthirty-.four VVinto .the counter .A by ,pressing the number two switch, S2, in the hundreds decade, the number three switch,-S3,

inthe tens decade, .and vthe number four switch, f

S4, in .the units decade. 4It should benoted that the number two hundred thirty-four, Aselected for purposes of the present explanation, -is the same as the number similarly chosen .in .the ygeneralized explanation above .setforth -It should also be pointed out that the counter Amay be calibrated .in foot candle-seconds,,lumen-seconds, or any other arbitrarilyselected unit of.measure ment which may lbe suitable.

`Thereupon, the reset-start switch Y'l .is closed energizing the solenoid vof thepowerrelayand closing thelock-Lin contacts I6, the'photocellcontacts 3l and .theoutlet contacts 38. Immediately the tubes Tlin each decade .are set upto `receive the initial count .and the coincidence tubes Ts are disposed in conducting conditionso that -the control relay will remain closed upon release ofthe reset-start switch 1. Thereupon, the light falling upon ythe `photocelll willcauseit'to conduct current finto the pulse generator 'I 3 :which will, rin

"14 turn, .begin-.to transmit :negative pulses into the units decade l-8 :along the input lead 22.

The input Avpulses will not necessarily be 'uniform in yterms of time, but will correspond `to units of light-quantity and these units will be counted yby the ring-of'dve vand scale-oftwo circuits inthe units decade V8. Every tenth pulsecoming into Ythe Aunits decade yWilL-as heretoforedescribed, initiate an interdecade transfer pulse which will be transmitted into the input lead 22 of .the tens'decade, nine, and-'every 'hun dredth impulseicoming into rtheunits 'decade will, similarly, .initiate an interd'ccade pulse which will be transmitted from .the tens decade, tinine, into the input lead 2-2 of Athe hundreds decade.

Meanwhile on every fourth :pulse 'coming .finto the unitsvdecade 8 the switch Si will function. as heretofore,generallyfdescribed in conjunction with the -coincidence tube T8 'to temporarily 'cut off -the -flowof current through the coincidence tube Tc to `the control .relay l5. This Qcurrent cut-off through the coincidence tube Tc of 4the units decade Will'o'ccur-on the fourth, fourteenth, twenty-fourth, thirty-fourth, and forty-fourth pulses vand so on up to and .through the two hundred thirty-fourth pulse coming into vthe units decade 8. Similarly, the switch S3 ofthe tens decade iwill Ifunction-in conjunction with the coincidence -tube Tc of such decade to 'interrupt the Vflow of its current .into -thecontrol relay l5 on .every thirtieth pulse coming into the units decade il, `that is to say, on yevery third .interdecade pulse transmitted -from the units ldecade 8 to the tens decade 9. As previously pointed out this cut-oifrconditionaof thecoincidence tube T8 in the tens Vdecade will vcontinue until the fourth interdecade pulse is received bythe tens decade fromthe units ldecade, or -in other words, until the fortieth pulse -is transmitted into the units decade Vfrom the pulse generator i3. Finally, the selector switch YS2 Aof the hundreds decade :I0 willoperat'ein1conjunction with the coincidence tube Taof such deca-de to interrupt the ilow of currentthrough -the'coincidence :tube T3 to the control relay i5 lon every second interdecade transfer pulse lreceived yby the hundreds decadefromthe tens decadeor, in other words,\on every two hundredth pulse coming into the units decade from the pulse generator 1.3. This cut-oil condition in the coincidence tube Ta 'of .the hundreds decade will continue until the -next interdecade `pulse :is received, but -in the present instance since the device is set :for the number two hundred thirty-four the entire operation will cease before such Ynext interdecade pulse is received. Actually, thecoincidence tube T8 of the hundreds decade dropsfinto off condition .at the two 'hundredth pulse and remains fof The device continuesfcounting,fhowever, and on the two hundred thirtieth pulse the coincidence tube Ta of the tens decade drops into ofi condition. Finally, when the -count'of two :hundred thirtyfour" is reached the coincidence tube T8 of the units decade `drops into on condition and -at this Vinstant all lcurrent vflowing into .the control relay l5 is interrupted simultaneously so the'corb trol relay I5 drops open.

As ythe control :relay I5 opens the ow of current to the lock-in switch -of the lrelay t6 is in terrupted and the relay I6 opens, immediately cutting oif flow of current to the photocell -2I and through the'outlet I8 to thesolenoid actuated shuttercf the lcamera. Thus, the camera shutter immediately'closes and the :flow ofpulses from the pulse'generator |i3 :into the units decade accanita `8*SceaseCSSnThe exposure isiconsequentiy "terrni nated automaticallyijwhena `volumef`-`of light equivalent to'two hundredV thirty-tour units has imp'inged upon the work being photographed. li for any reason it should be necessary or desirable to do so the exposure which was employed can be read, for ready reference, from the face of the counter A inasmuch as the counter-light Lzis lighted in the hundreds decade, the counterlightvlle' is lighted in the tens decade, and the counter-light'Li is lighted in the units decade. AIt will, of course, be evident that the counter A'is extremely simple and convenient to use since they desired end 'result may be set directly into the' rnachineV by depressing the 4appropriate selector switches in each decade. Furthermore, the counter A is substantially fool proof since it will readily reveal through observation 'of the lighted counter lights where 'any repair may be needed in lcase of mis-functioning. For example, if one ofthe tubes should happen to burn out anywhere in the counter A the device would stop functioning at some intermediate point short of the desired vresult and the configuration 'of the counterlights would serve as an immediate indication of thenatureand location of the diilculty. 'Y y 'f Y It should be understood Ythat 'changes and modifications in the form, construction, arrangement, and combinationof the several parts of the electronic counting device may be made and substituted for those herein shown and described without departingrfrorn the nature and principle of my invention."

Having thus described my invention, what I claim and desire to secure by'Letters Patent is:

l. An electronic device including aplurality of decades each comprising a ring-o-iive circuit, a scale-oi'f-two vcircuit in each decade, a coincidence circuit in each decade having an output lead and a control element so arrangedthat the coinci dence circuit will transmit electrical current to its output lead as long as the potential of the control element is in excess of a predetermined cut-oil potential, an isolating network in each decade having opposite input leads and an output lead connected to the control element of theocincidence lcir'cuit, ten Yswitches in each decade, each switch having two separate current paths therethrough respectively connected to the input leads of the isolating network, one of said paths in each switch being also connected to the scaleof-'two circuit and the otherpath being connected to the ring-of-ive, circuit, said switches being interconnected so that only one of them can be on at one time whereby to cause the isolating network to impose upon the control element of the coincidence circuit a potential substantially' below the cut-oil potential thereof responsive to a predetermined count, and a relay having an operating coil adapted upon being energized to hold the relay in a selected position, said operating coil being energizedin common through all the output 'leadsfrom the coincidence circuits of the decades sc that when all said coincidence circuits'areV biased oi coincidentally the relay will move out of said selected position.

2. An electronic counter including a plurality of decades each decade including a ring-of-nve circuit comprising ve cascaded trigger circuits, a scale-of-two circuit, a coincidence circuit associated with each decade and having an output lead and a control element so arranged that the coincidence circuit will transmit electrical cur'- rent to its output lead as long as thepotential of the control elementisdn `excess of a predetermined cut-of potential, an isolating network associated with each decade and `having"opposite input leads and an output :lead connectedtothe control element of the"coincidencgcircuim ten switches 'each of: saidswitches Ahaving Vtwo 'sepa rate pairs'bf contact-elements, the contact-elements ofeach'pairbeing optionally connected by al contact-blade, Ythe contact-blades of "each switch being mechanically `connected, foi-simultaneously opening and closing, thereby establish@ ing` twoe-distinct5-current -pathsf through each switch, one contact-element of each Ypair within eachsuch switch being -respectivelyconnected to theinput leads ofthe isolating network, the other contact-element of-onepair withineach switch being connected tof the-scaleoftwo circuit`V and the other contact-element of the other lpair being connected to a selected trigger circuit in Mthe ring-of-iive-I circuit and -being ai so-y arrangedg-that eachV trigger circuit `is connected to =two diierent switches, saidswitches .being interconnectedso .that only one 4of, them can-.be ffonat one time whereby to cause thefisolating network to impose upon `the controllelement. of the coincidence-circuit a potential substantiallybelow theYcut-oi potentialthereof responsive to .a predetermined count, anclaJU single. rrelay commonhto all the decades, .said relay having, an operating coil adapted upon beingenergized to'hold theV relay in a selected position, saidoperating coil being energized in common through all the output leads from the coincidence circuitsv of the'several'decades so that when all-,saidcoinci'dence Acircuits are biased ol coincidentally the relay will move out of said selected-position.VVV

3. An electronicv counterfincluding a plurality of decadesv each decade jincluding. a ring-of-ve circuit comprising ve cascaded trigger circuits. a scale-.of-two'circuit, a 'coincidence circuit" associated with Veach vdecade and having 'an output lead and a control element so arrangedthat the coincidence circuit will transmit electrical current to Vits output lead as long as' the potential of the control element is in excess of a predetermined cut-off potential, an isolating network associated with each decadeV and having opposite input `leads and anoutput lead connected to the control element of the coincidence circuit,r ten Switches @ech 0f said SWiheShaYins worsenerate pairs of contactjelements, thencontact-elements -of eachpairrbeingj optionally connected bya vcontact-blade, the 4contact blades of each switch being mechanically Qnnected'fcf sirhultaneously opening arnclgclosing,` therebyestab-v lishing two distinct current paths kthrough each switch, one contact-elementof each pair within each suchswitch being respectively connectedfto the inputleads of the isolating network, Ythe other contact-element or one .painwithin each switch being {connectedto ,the scale-of-.two cir-V cuit and the other contact-element of the other pair being connected to a selectedtrigger circuit inthe ring-of-ve circuit and being so .arranged that each trigger circuit is connected to two .dif- Iferent switches andonly l ,two, said switches being mechanically interconnected so that only one of themcan be on at one time whereby tocause the isolating network v to impose upon the con-. trol element of the 'coincidence circuita potenaai supstannauy below the cut-01T .potential thereof responsive to a predetermined count, and a single relay common to all' the decades Asaid relay having an operatngcoil adapted upon being energized to holdthe relay in aselected position, saidoperating coil' being energized in common l? through all the output leads from the coincidence circuits of the several decades so that when all said coincidence circuits are biased 01T coincidentally the relay will move out of said selected position.

4. An electronic device including' a ring-of-ve circuit having iive cascaded trigger circuits arranged as iirst, second, third, fourth, and fth trigger circuits, respectively, means for imposing an impulse upon the first trigger circuit, a u

scale-of-two circuit operatively connected to the fifth trigger circuit, a coincidence circuit having an output lead and a control element so arranged that the coincidence circuit will transmit elecf trical current to its output lead as long as the potential of the control element is in excess of a predetermined cut-ofi potential, an isolating network having opposite input leads and an output lead, said output lead being connected to the control element of the coincidence circuit, and ten switches each of said switches having two separate current paths therethrough respectively connected to the input leads of the isolating network, one olf said paths in each switch being also connected to the scale-of-two circuit and the other path being connected to one of the trigger circuits in the ring-oi-five circuit, said switches being interconnected so that only one of-thern can be on at one time whereby to cause the'isolating network to impose upon the cont-'rol'element of the coincidence circuit a potential substantially below the cut-off potential thereof responsive to a predetermined count.

5. In an electronic device including a plurality of decades arranged in successive order each f decade comprising a ring-of-flve circuit, a scaleof-two circuit associated with each ring-of-ve circuit, a coincidence circuit associated with each decade having an output lead and a control element so arranged that the coincidence circuit will transmit electrical current to its output lead as long as the potential of the control element is in excess of a predetermined cut-off potential, a "discriminating circuit having an input lead from the scale-of-two -circuit and an output leadto the ring-of-vercircuit of the next successive decade, an isolating network associated witheach decade having opposite input leads and an output lead connected to the control element of the coincidence circuit, ten switches each of said vswitches having two separate current paths therethrough respectively connected to the input leadsof the isolating network, one of said paths in each switch being also connected to the scale-of-two circuit and the other path being connected to the ring-of-ve circuit, said switches being interconnected so that only one of them can -.be .on at one Atime whereby to cause the isolating network to impose upon the control element of the coincidence Icircuit a potential substantially below the cut-or potential thereof responsive to a predetermined count, and a relay having an operating coil adapted upon being energized to hold the relay in a selected position, said operating coil being energized in common throughall the output leads from the coincidence circuits of the decades so that when all said coincidence circuits are biased oir coincidently the relay `will move out of said selected position.

6. In an electronic device including a plurality of decades arranged in successive order each decade comprising a ring-of-ve circuit,

ascale-of-two circuit associated with each ring- Y of-ve circuit, av coincidence circuit-associated with each decade having an output lead and a control element so arranged that the coincidence circuit will transmit electrical current to its output lead as long as the potential of the control element is in excess of a predetermined cut-0i`f potential, a discriminating circuit having an input lead from the scale-oitwo circuit and an output lead to the ring-of1ve circuit of the next successive decade, an isolating network associated with each decade having opposite input leads and an output lead connected to the control element of the coincidence circuit, and ten switches each of said switches having two separate current paths therethrough respectively connecte-:l to the input leads of the isolating network, one of said paths in each switch being also connected to the scale-of-two circuit and the other path being connected to the ring-ofve circuit, said switches being interconnected so that only one of them can be on at one time whereby to cause the isolating network to impose upon the control element of the coincidence circuit a potential substantially below the cut-oil potential thereof responsive to a predetermined count.

7. An electronic device comprising a sensory circuit capable of emitting an electric current directly proportional to an observed physical phenomenon, a pulse generator adapted to emit a series of discrete electrical impulses related to each other in terms of time so as` to be directly proportional to the integral of the observed physical phenomenon producing the electrical current emitted by the sensory device, a countingcircuit consisting of a plurality of decades, each decade including a ring-of-rive circuit and a scale-oftwo circuit interconnected for emitting an electrical impulse responsive to every tenth impulse received from the pulse generator, a coincidence circuit associated with each decade, ten switches associated with each decade and being interconnected so that only one switch can be on at any one time, each of said switches being so arranged as to transmit an impulse responsive to a selected incoming impulse from the pulse generator, and an isolating network adapted for receiving the impulse from the selected switch and imposing such impulse upon the coinciden-ce circuit.

8. An electronic device comprising a sensory circuit capable of emitting an electric current directly proportional to an observed physical phenomenon, a pulse generator adapted to emit an electrical impulse each time a predetermined quantity of electric current is fed into it from the sensory device, a counting circuit consisting of a plurality of decades, each decade including a ring-of-ve circuit and a scale-of-two circuit interconnected for emitting an electrical impulse responsive to every tenth impulse received from the pulse generator, a coincidence circuit associated with each decade, ten switches associated with each decade and being interconnected so that only7 one switch can be on at any one time, each of said switches being so arranged as to simultaneously transmit current from the ring-offive circuit and scale-of-two circuit responsive to a selected incoming impulse from the pulse generator, an isolating network adapted for simultaneously receiving the current transmitted by said selected switch, means in the isolating network for generating a resultant potential responsive to the imposed potential received from the selected switch, and in turn imposing such generated potential upon the coincidence circuit.

`9. An electronic instrument comprising a sensory circuit capable of continuously emitting an electric current instantaneously and directly proportional to an observed physical phenomenon, a pulse generator adapted to emit an electrical impulse each time a predetermined quantity of electrical current is fed into it from the sensory device, a plurality of interconnected counting decades each counting decade consisting of a ring-of-ve and scale-of-two circuit adapted to emit an electrical impulse responsive to every tenth impulse received from the pulse generator, a coincidence circuit associated with each decade counting circuit, said coincidence circuit comprising a triode tube having a cathode plate and grid, a control relay adapted to respond to the counting circuit in a predetermined manner, said control Vrelay being connected to the plate of each coincidence circuit in each decade, ten switches associated with each decade, said switches being interconnectedso that only one of them may be on at any one time, each of said switches being adapted when on to simultaneously transmit t current from the ring-of-ve circuit and scale-of-two circuit responsive to selected incoming impulses from the pulse generator to the exclusion of other incoming impulses, an isolatingl n etwork connected to the switches and arranged to transmit current responsive to thecurrents simultaneously received from the selected switch which is in on position when the device is op-A erating, saidisolating network being also connected to the grid of the coincidence circuit associated with its particular decade for imposing a potential upon the grid responsive to the currents receivedfrom theV particular switch which isvin"on position, and being adapted to cause said tube to'cut-ofi responsive to one unique impulse out of every series of ten impulses received Y by such decade from the pulse generator.V

10. Ina device of the characterfdescribed a counting circuit consisting of five individual trigger circuits successively connectedso that-the input sides of each circuit are connected in common to a commoninput lead, an output lead fromV each trigger circuit connected to the next successive trigger Circuit S9 ihatthe flv ifggercrsuitsare connected in a continuous ring and are adapted to successively condition each other for the trans-I mittal of a-conditioning impulse Vinto the successive trigger circuit whereby the first impulse appearing on the common input lead willinvert the first trigger circuit andrwill cause it to transmit a conditioningv impulse into thenext successive trigger circuit so that such next successive trigger circuit will be affected by the secondimpulse appearing on the common input lead,

an independent trigger circuit connectedto the Y fifth one of the above named trigger circuits and adapted to receive the output impulse therefrom so as to be inverted by the first such impulse received and adapted to transmitan output impulse responsive'to the second impulse thus Vreceived whereby the independent trigger circuit' will transmitan output -impulse responsivejto every tenth impulse'appearing on the common input lead, and Yten single` throw double pole. switches associated with the ring-of-ve circuit,4

A' y the other poles vof each pair of switches being refj spectively connected to the opposite side ofthe; independent trigger circuit, means for interconjV necting said switches so that only one of them4 may be on at any one time, an isolating network connected across every one of said switches-.-

so that the current from one selected trigger circuit in the ring-of-five and the current from the independent trigger circuit will be simultaneously` imposed upon opposite sides of the isolating network, an output line from the isolating networlg:

imposed on the grid by the isolating network is below such established cut-01T potential, and

means connected to the coincidence tube actu-y able responsive to the cutting-off of said coincidence tube.

l1. In a decade counter consisting of -a ring-'of-jfive circuit and a scale-of-two circuit the prof vvision of direct presetting to a desired numberY which comprises a relay adapted to be actuated by the counter, said relay having one terminal connected directly to ground, a sourceof operat ing potential having twoterminals one of which, is also.Y connected to ground, a coincidence tube havinga grid, aplate, and -a cathode, said plate being connected to the other terminal o the relay and said cathode being connected to the other terminal of the source of potential, ten double pole single throw selector switches each having first and second input poles and first and second. output poles, saidswitches being paired `by the vini-- tercorinection in.V common of the first input-politeofy eachvswitchin such pair and the common connection in turn ofsuch first inputpoles to the out-Y I putside of lone of the tubes thering-of-vecir-I cuit each pair-of switches vbeing'thus connected to a different one of thefivetubesin the ring-of-ve' circuit, an isolating network havingone-side connectedcommon toall'of the first output poles of all ten switches and itsother side c on nected in common to all ofthe second output poles of all of the ten switches, said isolating net'- work having anelectrical center point which is connected to the grid of the coincidence tube, and

means for interconnecting all ten switches so` that only one of them canbe in on 'position' at any one time, the second input pole or" one pair of switches being connected to one -side ofthe scale.`

of-,two and the Vother second input pole of the otherswitch in each pair being connected to the other side ofthe scale-of-two circuit so that when' anyselectedswitch isplaced in on positionrit will simultaneously impose Yuponthe ,isolating network a potential from the `scalefof-,twocir-`V cuit and a potential from one of the tubesin the.. ring-,ofA-vecircuit, such potentials respectivelybeing adapted to change sharply as such'tubes-in j scale-of -two cirdiode and a thyratron operatively connectedto,v

the condenser, said gas diode being also connected to the grid of the thyratron so that whenthe diode res the potential transmitted thereby will bei, imposed on the thyratrongrid, causing .the thyra-v tron in vturnto fire and thus discharge'thescon condenser to reach the predetermined value at` which it is discharged.

13. For use with a sensory device capable of emitting an electric current responsive to an observed physical phenomenon, an electronic integratr comprising a capacitor adapted to receive a charging current impressed upon it by said sensory device, a gas diode connected across the capacitor and having a predetermined ignition ptential at which it will initiate discharge of the capacitor, and a thyratron having a plate and cathode respectively connected across the capacitor and having a grid capacitatively connected to one side of the diode so that the diode will nre when the charge in the capacitor reaches said ignition potential and will in turn cause the thyratron to fire, discharging the capacitor, said thyratron having an extinction potential such that it will terminate the discharge of the capacitor substantially at zero potential.

11i, For use with a sensory device capable of emitting an electric current responsive to an observed physical phenomenon, an electronic integrator comprising a capacitor adapted to receive a charging current impressed upon it by said sensory device, a gas diode connected across the capacitor and having a predetermined ignition potential at which it will initiate discharge of the capacitor, and a thyratron having a plate and cathode respectively connected across the capaci-- tor and having a grid capacitatively connected to one side of the diode so that the diode will nre when the charge in the capacitor reaches said ignition potential and will in turn cause the thyratron to fire, discharging the capacitor, said thyratron having an extinction potential such that it will terminate the discharge of the capacitor substantially at Zero potential, said extinction potential of the thyratron being lower than the extinction potential of the gas diode.

15. For use wih a sensory device capable of emitting an electric current responsive to an observed physical phenomenon, an electronic integrator comprising a capacitor adapted to receive a charging current impressed upon it by said sensory device, a gas diode connected across the capacitor and having a predetermined ignition potential at which it will initiate discharge of the capacitor, and a grid-controlled gas discharge tube having a plate and cathode respectively connected across the capacitor and having a grid capacitatively connected to one side of the diode so that the diode will nre when the charge in the capacitor reaches said ignition potential and will in turn cause the thyratron to nre, discharging the capacitor, said thyratron having the characteristic that its extinction potential is reproducible with substantial uniformity in each of its successive operations.

16. An electronic instrument comprising a sensory device capable of continuously emitting an electric current instantaneously and directly proportional to an observed physical phenomenon, and a pulse generator adapted to emit an electrical impulse each time a predetermined quantity of said electrical current is fed into it from the sensory device, said pulse generator comprising a capacitor circuit, a gas diode connected across the capacitor circuit, a thyratron 'A also connected across the capacitor circuit, saidI gas diode being also connected to the grid of the thyratron so that when the diode `iires the potential transmitted thereby will be imposed on the thyratron grid, causing the thyratron in turn to nre and thus discharge the capacitor circuit when a predetermined quantity of electrical current is' stored in the capacitor circuit, said thyratron thereupon transmitting a single output pulse at the vtime of such discharge, and a double triode having one grid connected to the thyratron for receiving the output impulse therefrom and being Yadapted for extending the duration of said output impulse.

17. For use with a sensory device capable of emitting an electric current responsive to an observed physical phenomenon, an electronic integrator comprising a capacitor adapted to receive reaches said ignition potential and will in turncause the thyratron to lire, discharging the cal. pacitor, said thyratron having an extinction potential such that the discharge of the capacitor will be terminated substantially at zero potential,

said thyratron having its plate connected to one side of the capacitor and its cathode connected to l Yone side of a resistor, the other side of said resistor being connected to the other side of the capacitor, and a double triode having one grid ca-v pacitively coupled to the thyratron-capacitor circuit between the resistor and the capacitor, for emitting a negative impulse responsive to discharge of the capacitor, the duration of which negative impulse is extended in relation to the discharge-time of the capacitor.

18. An electronic instrument comprising a plurality of identical counter-decades, each decade including a ring-of-ve and scale-of-two circuit, said decades being arranged in successive ascending orders of tens, an interdecade transfer circuit interposed between the successive decades so that every tenth impulse entering the units decade will be transmitted into the tens decade and every tenth impulse coming into the tens decade will be transmitted into the hundreds decade and so on in powers of ten to the highest decade, a switching circuit in each decade, said switching circuit comprising ten switches corresponding respectively to the integers from Zero to nine, an isolating network having input leads and an output lead, said switches being connected across the ring-of-ve and scale-of-two circuit and the input lead of the isolating network in such a manner that when a switch corresponding to a selected integer is closed an output signal will appear upon the output lead of the isolating network every time the ring-of-nve and scale-of-two circuit receives an input pulse corresponding to said integer in the sequence of counting, a coincidence circuit in each decade, said coincidence circuit having an output lead and an input lead, the input lead of the coincidence circuit being connected to a source of current supply and the coincidence circuit being adapted normally to pass current through to the output lead continuously while the counter is in operation, a control element in each coincidence circuit of each decade connected to the output lead of the isolating net- Work inthat decade and arranged so that when an impulse appears on the output lead of the.

of the output leads of t'ne several coincidenceV circuits of the several decades so that said actu-` ating coil will be energized when any one or more of the coincidence circuits is in conducting condition and correspondingly will become de-energized only when all of the coincidence circuits simultaneously `become non-conducting, and means operatively connected to the relay producing a desired result responsive to deenergiza tion of the relay-actuating coil.

, 19. An electronic instrument comprising a plurality ofcounter-decades, each decade including a ring-of-ve circuit, a scale-of-two circuit, a coincidence circuit having an output lead and a switching circuit also having an output lead, said coincidence circuit being connected to a source of current supply and being adapted normally to conduct current continuously to its output lead While the counter is in operation, said switching circuit being connected to the ring-of-ve and scale-oftwo circuits in such a manner as to produce a unique impulse upon its output lead responsive to a pre-selected count, each coincidence circuit in each decade having a control element connected to the output lead of the switching circuit in such decade, said control element being arranged to render the coincidence circuit non-conducting when an impulse appears on the output lead of the switching circuit and hold the coincidence circuit in non-conducting condition until the next count appears in the ring-of-ve circuit, and .a

relay having an actuating coil connected on one side to a source of current and on its other side in common to all the output leads from all the coincidence circuits in several decades inY such manner that the actuating coil Will beenergized when any one or more of the coincidence circuits is conducting and will correspondingly becomedeenergized only when all of the coincidence circuits are simultaneously in non-conducting condition.

PHILIP GILBERT.

References cited in che nie of this'patent UNITED STATES PATENTS OTHER REFERENCES Electronic Counters, I. E. Grosdoii: "R. C. A. Revievv; September 1946; vol. VII, No. 13; pages 438-447 Predetermined Counter; R. J. Blume: Electronics; February 1948; pages 88-93.

Video Program Recording; Gillette et a1.: Electronics; October 1950; pages 90-95.

Reference Data for Radio Engineers; Federal Telephone and Radio Corp., New York, N. Y. 1949; page 270, Fig. 22. Y 

